you have orders to give a patient 20 mg of a certain medication the medication is stored 4 mg per 5 ml dose how many milliliters will need to be given

HESI A2

HESI A2 Math Practice Test 2022

1. You have orders to administer 20 mg of a certain medication to a patient. The medication is stored at a concentration of 4 mg per 5-mL dose. How many milliliters will need to be administered?

A. 30 mL
B. 25 mL
C. 20 mL
D. 15 mL

Correct answer: B

Rationale: To administer 20 mg of the medication, you would need 25 mL. This calculation is derived from the concentration of 4 mg per 5 mL. By setting up a proportion, you can determine that for 20 mg, 25 mL must be administered as follows: (20 mg / 4 mg) = (x mL / 5 mL). Solving for x results in x = 25 mL. Choice A is incorrect because it miscalculates the proportion. Choices C and D are incorrect as they do not account for the correct concentration of the medication.

2. How many meters are in 3000 millimeters?

A. 3 meters
B. 30 meters
C. 0.3 meters
D. 300 meters

Correct answer: A

Rationale: 1 meter is equal to 1000 millimeters. Therefore, to convert 3000 millimeters to meters, we divide by 1000. 3000 millimeters / 1000 = 3 meters. Choice A, '3 meters,' is the correct answer. Choice B, '30 meters,' is incorrect because it represents a miscalculation of multiplying instead of dividing. Choice C, '0.3 meters,' is incorrect as it is the result of a decimal error. Choice D, '300 meters,' is incorrect as it is a result of not converting millimeters to meters correctly.

3. Solve for x: 3(x - 4) = 18.

A. x = 10
B. x = 12
C. x = 5
D. x = 3

Correct answer: A

Rationale: To solve the equation, begin by distributing the 3 on the left side: 3x - 12 = 18. Next, add 12 to both sides to isolate x: 3x = 30. Finally, divide by 3 to determine the value of x: x = 10. Therefore, the correct answer is x = 10. Choice B, x = 12, is incorrect as the correct value of x is 10, not 12. Choice C, x = 5, is incorrect as it does not satisfy the equation after substitution. Choice D, x = 3, is incorrect as it does not fulfill the equation when substituted back.

4. What is the result of subtracting 9.99 from 12.02?

A. 2.03
B. 2.21
C. 3.17
D. 7.97

Correct answer: A

Rationale: The correct subtraction is 12.02 - 9.99 = 2.03. Therefore, the correct answer is A. Choice B, 2.21, is incorrect as it does not result from the given subtraction. Choice C, 3.17, is also incorrect. Choice D, 7.97, is incorrect as well. Thus, A is the only correct answer.

5. A doctor orders 1 gram of a medication to be administered intravenously. The available vial contains 200 milligrams per milliliter. How many milliliters of the solution should be drawn up?

A. 4 milliliters
B. 5 milliliters
C. 10 milliliters
D. 20 milliliters

Correct answer: B

Rationale: 1 gram is equivalent to 1000 milligrams. The concentration of the medication is 200 milligrams per milliliter. To calculate the volume needed, divide the total amount of medication by the concentration: 1000 mg / 200 mg/mL = 5 mL. Therefore, 5 milliliters of the solution should be drawn up to administer 1 gram of the medication intravenously. Choice A (4 milliliters), Choice C (10 milliliters), and Choice D (20 milliliters) are incorrect because they do not accurately calculate the volume of the solution needed based on the concentration of the medication.